Clutch with synchronizing means



May '21', 1935. J. P. RUTH ETAL CLUTCH WITH SYNCHRONIZINQ MEANS FiledNov. Y, 19.55

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Patented May 21K, 1935 Joseph P. Ruth and ver, Colo., assignors- 4George H. Woelbing, Dento The Ruth C'ompany,'

Denver, Colo., a corporation of Colorado `Appnsatian Nevember 7, i933, serial No. 696,991V

3 claims.

This invention relatesv to improvements in shaft coupling mechanisms and has reference more particularly to a shaft coupling device which is adapted to form part of a transmission gear mechanism of the type interposed between an engine and a drive axle for .the purpose of changing the gear ratios. f

d In many types of machinery it is a great convenience toibe able to directly couple afdriving lo' shaft to a ,power transmission member `while 4the shaft is rotating and whenever clutches of the claw type `or which employ intermeshing teeth are used, it is impracticable to interconnect the two parts while they are rotating relative to each other, especially where the power transmission member is conneeted tosome machinery thatre- `quires considerable force `to move .it because the sudden interconnection of the driving and the drivenmembers would 'be resisted by the 'inertia 2o of the :parts of the driven mechanism and the shock due to such.sudden:interconnection would produce strains that would break the machinery.

In all positively interconnectedclutches `andin transmission gears, the interconnectionmus't 'take z place either when the parts are standing `still or rotating at such relative speeds that the :interconnecting teeth" will move at the same speed so asto permit them out clashing. i

`In theordinary transmission `gears employed onautomobiles, the shifting ofthe gears forthe purpose of varying the gear ratios takes `place only after the-engine andthe car have attained such relative speeds that this shifting cantake 5 place without shock. i l Ithas recently become the practiceto provide transmission gears with a synchronizing :clutch 4mechanism that will bring the positivevdriveY clutch membersinto synchronismbefore'the posi. i itivefdrive connection `is effected and this Lsimplie` 4fies theoperation of gear shifting becauseif 'the parts are properly constructed and'functionas in- Vtendedthe positive drive connection canbe made when `therelativespeedibetween thedriving and the driven parts is suicientto prevent disastrous results. L' i It is the `olcject'of this invention topr'oduce a clutch of the positive drive type Whichshall be provided with a synchronizing ciutchof such constructionv that it will moveto operative position and function fas a frictionclutchwith suii'icient power to produce synchronism ofthe 'relatively movable parts before the teeth of the `positive drive .clutchioome into engagement andthenrelease the friction drvelso fas to .allow suicient vto'be brought into" mesh with-` relative :rotary `movement of the parts to permit the clutch` teeth to mesh before they can enter into interlocking engagement.

Another object of this invention is to produce a positive drive clutch with synchronizing means `5 that can be .employed either in connection with a single powertransmission member or in connection with two separate power transmission members, either of whichcanv be independently connected.4 s I Another object of this invention is to produce a clutch ofthe typedescribed which shall be especially well adapted for heavy duty work, as, for example, in connection with the gear transmissions interposed between an internalcombustion 15 engineand the drive wheels of a locomotive.`

The above and .other vobjects that may .become `apparent as this description proceeds are attained by means of a constructionand Yan arrangement of f parts that will now be described in'detail, and for this purpose, reference will be had to .theV 'accompanying drawing in which -the ipreferred embodiment of the invention has been illustrated, and in which: i

`IFig.. `1 vis a rlongitudinal section throughthe 25 clutch :mechanism that forms the `subject of this invention;

Fig. 2 fis a `transverse section `taken on line 2 2, Fig. 1, and shows some ofthe parts in section, while others are shown in elevation, parts Vhaving been broken away, to simplify the idrawing as they are merely duplicates of thexparts shown;

Fig. 3 is a view looking in the direction/oferrow `3, Fig. 1, and shows the outer surfaceof one ofthe 'friction shoes;

= Fig'. 4 is a section somewhat similar to lthat shown in Fig. `1 and shows the latching `and Vunlatching `means to ai somewhat enlargedfscale; vi'ig. 5 is :a view lookingin Athetdirection` `of arrow, Fig.4'; f E y.

Fig. 6 is a sectiontaken lonline 6 6, Fig. 5;

Fig. 7 is a side elevation cfa gear `transmission showing 'the Arelative locationfof the parts.

.Inlthe drawingreference numeraldesignates the drive shaft, while reference numeralf` designates the driven shaft. The `use oftwoeparallel vshaftsfis'not essential,` but areV employed in th'e particular construction in which the .invention is embodied at presentybut it is to `be 'understood 50 that the'device `can be employed fortransmitting power between two aligned rshaft sections in a'. manner which lwillbe :hereinafter explained.

The drive shaft has securedto it 4two "spur gears I0 and LI {,and these gears'are somounted 55 that they have neither rotary nor longitudinal movement on the shaft. Carried by the driven shaft 9, are two spur gears Illa and lla, which are normally in mesh with gears IE! and Il respectively. It is evident that if the shaft 8 rotates at a constant speed and power is transmitted from it to shaft 3 through the gears i!) and Ia, the shaft S will rotate faster than shaft 8 because the spurgear IB is larger than the gear ma, whereas ifV power is transmitted through gears Il and Ha shaft 9 will rotate at a slower rate because the Ha and therefore by providing some convenient means for interlocking either of .the gears Ilia or Ila with the shaft 9, 'the gear ratio between shafts 8 and 9 can be changed.

Referring now more particularly to Figs. l and 2, it will be seen that there has been slidably mounted on the shaft 9, a clutch member l2. lIhis clutch member is held against relative rotation on the shaft by means of three or more keys I3. The ends of the clutch member are provided with teeth i4 between which are the recesses i5 by which the teeth are separated. The gear ma is provided on the end adjacent to thek clutch member with teeth It which are properly shaped and positioned to interlock with the teeth i4 in a manner well understood. The gear lila has secured to the side adjacent the clutch member l2 a ring H that has an inner cylindrical surface I8 which will be referred to as a friction surface. This ringjmay be secured to the gear in any suitable mannenbut has been shown as connected to the gear by means of a threaded connection I9`A and pins 20. In the particular embodiment illustrated, the power transmission member lia has been shown as provided with a friction surface 2l that corresponds to friction surface i8 on the power transmission member ma. The power transmission member lla is also provided with teeth I8 like those on the other power transmission member and these in turn are designed to intermesh with the corresponding teeth I4 on the clutch member.

The clutch member is provided with outwardly extending radialv arms or spokes 22, whose outer ends are joined by a ring 23 that is provided on its outer surface with a groove 24. A collar 25 that has an inwardly extending flange 26 of theproper size to t the groove 24 is put into place about the ring 23 and the two parts of this collar are held in assembled position by means vof boltsy 2l' as shown most clearly in Fig. 2. Each of thev collar parts is provided with a trunnion 28 with which the ends of the shifting fork are connected. The shifting fork has been shown inFigJ? where it has been designated by reference numeral 29. 'This fork is pivoted at 30 and has twov arms 3l' .provided with bearings that cooperate with the trunnions 28 inthe manner usual in suchccnstructions.

It is now evident'that with the parts which have'alrea'dy been'described, it is possible to interconnecti the shaftl' withv either one of the power transmission members ma. or i la by merelyshifting the clutch member l2. In Fig. 1 the shaft has been shownas positively connected to the power transmissio'nmember i lo', and by movingI` theV clutchv memberl I2'towards the left a sucient dirstancait^ is possible to release the connection between the shaft and transmission member Ha and to` establish a similar driving connection between the shaft and theV `transmissionmemberia.

Although a driving connection 'can'be estabgear Il is smaller than gear lished by the parts already described, it is apparent that it would be impracticable to operate the clutch mechanism while the shaft 9 was turning unless the power transmission member to which connection were to be made was rotating at a speed substantially synchronous with the speed of the shaft and means has theretofore been provided to secure such synchronous rotation before the driving teeth are moved into interlocking engagement.

VThe synchronizing clutch which will now be described consists of a central ring formed of tw sections 32 and 33. These rings are practically identical in construction and are provided with inwardly extending spacing lugs 34 which project through the openings between the spokes 22. The lugs 34 have offset portions like those shown in Fig. i that hold them in alignment. On each side of rings 32 and 33 is an angle ring 35. The rings 32, 33 and 35 are held in assembled position by means of rivets 36 that pass through the lugs 34 and through the radial flanges of the angle rings in the manner shown quite clearly in Fig. 2.

. The horizontal flanges of rings 35 are provided with circular grooves 31 on their outer surfaces for a purpose which will appear as the description proceeds.

The rings 32 and 33 are held against relative rotation with respect to the clutch member by means of keys 38. For the reception of these keys; the spacing lugs 34 are provided with key slots on their inner surfaces as shown in Fig. 2 and the clutch member is provided with corresponding key slots in its outer surface.

In the construction shown there are nine radial arms 22 and nine spacing lugs 34 and there are nine keys 33 employed in the particular construction shown. The keys 38 are each provided on their under side with a longitudinally extending key slot 40 and also with two spaced transverse slots 4I. Located in the key slot 4B aretwo latch releasing members 42. "fheseV latch releasing members are provided with portions 43 that fit the slot 40 of the key 38 and these portions are each provided with a notch 44 having one wall inclined as indicated by reference numeral 45. The combined length of the latch releasing membersv is somewhat greater than the distance between the outer flanges of the angle rings 35 as shown in Fig. 4. The clutch member is provided with a radial opening 46 corresponding 'to each'key 38 and is also provided with a key slotr 41 with which the key 38 cooperates. Each of the radial openings has a spring 48 that serves to force a'steel ball 49 outwardly against the under surface of the key 38. When the ball is located at the intersection of the slots 4B and 4|, it will be in the position shown in Figs. 4 and from which it will. be seen that the depth of the notches 44 is equal to the radius of the ball and therefore when it is in the position shown in Fig. 4, the clutch member l2 and the key 38 are positively held against relative movement, but if pressure is applied to the end cf member 42 that projects to the left in Fig. l, the inclined wall 45 will function to move the ball downwardly so as to release the latch. The purpose of this latching device will appear more fully as the description proceeds. The spacing lugs 34 are provided on their outer surface with transverse grooves 50 which are adapted to receive the projecting rib 5l on the inside of each friction shoe 52. One of the friction shoes 52 has been shown in elevation in Fig. 3 from which rzgoo 1,1892

,. portion 53.A Each friction :shoe ffis` provided near veach end lwith` .a1 groover54= thatfservesffor:V the reception of v tension springs ."55 whosei'function --it a is to;:hold. them inposition againstwthe toggle links 56 by means of whichthe frictionfshoesgare `supported.` 'Thezinside surfaces of therparts 52 have `grooves :51 `in awhich the 'outeri endsy of 1 theftoggle links @56 `frest.

Since lthe. toggle .links form van xunstablefsupport fors: the :friction shoes, `itis `eviwdent thatrtheaction Tthe i-shoes inwardly :until .they seatragainst the of the. springsan55 `willbring :solidnsurfaceof theringsi32 Iand 33 Aand-the toggle nlinksfwill befinclinedin one direction onthe: other, vdepending.uponithe positionof.; the` clutch.

`positionshown in Fig. 1`

Let rus ;now i assume :that :the lparts'l are `in #the and that `Lit .is desired to `change `the `:gear ratio lby bringing the `clutch member :I2

into driving connection with ,fthe

130werftransmissionimember` Iia. Whenl this shift ,gis-.toxbe;accomplished, ;the-operator exertsfa force :on the shift leverV 29 which moves `:the clutch member =I;2 towards the .leftra sufficient distance l to :disengage the ,teeth z I4 :from :the :cooperating :teeth `of `the :power The f clutch rwill -now an instantand as'theclutch member "moves far- `.therntoward the left,

transmission :member I la, be :in .neutral .position :for

the friction surface :'-52 I of 'each shoefmiprojectedinto theiflangefITssoas to overlap ythe `friction :surface tI8 .and :when the -rnovementfhas progressed sufficiently for 'they yend the toggleilinks 56 restwill continue their movef as new'is:`

' :surface P58 ito `strike fthe ishoulderiat :the .inner friction-surface 8,1the shoe will cease and33 on which end of the to move, whereas, the rings 32 mentwiththe resultjthatfangularity of the toggle links will approach ninety degrees and this will force the surfaces 52 against the friction surface tion to bring the flange II and tance from each other transmission member Y but with the pressure and fricthepower transmission member IIJa to which it is connected into synchronism with the shaft. When the toggle links are in vertical position the ends ofthe teeth I4 and I 6 will still be spaced a short disand will therefore not come into contact until the parts have moved a further distance, whereupon the toggles will inoline in the opposite direction from that shown in Fig. 1 and release the pressure, thereby permitting relative movement between the power and the clutch member, but as this release also decreases the force that must be applied to the shift lever 29, the clutch member I2 will move at increased speed towards the power transmission member, but before the teeth I4 and I6 come into engagement, theend of member 42 will strike the adjacent surface of the ange member I1 and force the ball 49 out of latching position, and thereby permit the clutch member I2 to move freely into interlocking position in which position the ball 49 will be in contact with the other transverse recess 4I in a position corresponding to that shown in Fig. 1,

parts engaging the power transmission member IIla instead of power transmission member Ila.

At this point attention is called to the fact that I8 thereby producing sufficient `inthe operation of this device the synchronizing -clutch comprising the friction shoes and the friction surfaces v operative position, whereupon the friction shoes are stopped by their interengagement with the l mission member so as toV @when fthey are Vbrought clutch mechanism described for making.' connectionvbetween a rotating shaft and fapowerltransmission member rotatably mounted thereon, that the power transmission member the device-usedffor connecting l' device isnot intended 'in lFig. "7 and that it ing synchronous clined that their outer ends i end surfaces of the clutch transmission member having cooperating teeth I8 and 2 I is first brought into proper` unember fand the friction shoes fwhich angularity of the toggle exerted on -tl'iesynchronizing clutchis the` great- 1 est, .the `interlocking `teeth are still spacedf some :distance apart and `that when'further 'movement if# is made, the synchronizing clutch is released thereby permitting slight relative rotation beweenithe clutchunember and the power transpermit the teeth to mesh together. release of 1 the 1 force that had been exerted on the synchronizing clutchfpermitsthe parts to move quicklyl until the adjacent edges `locking teeth are about to `interlock when the `slatching:mechanism will Vbe suddenly released, :thereby permitting full interlock between Vthe of the interclutchY member memben y 1 i It iis evident that instead of employing the the purposeiof and the power transmission canlbe connected to an aligned shaft section and aligned shafts Lwhile the power shaftis operating. i

It iis rto be understood that the use of this to `be limited Vfor transmission :gears i havingl parallel shafts like that shown is adapted for-many other ses o-fwhich the one illustrated ismerely an example. A 'l IHaving described the invention what is .claimed 1. In a clutch mechanism of the type employed for making a direct and positive driving connection between a shaft and a power transmission member rotatably mounted thereon and which includes a clutch member slidably but nonrotatably mounted on the shaft and means for obtainrotation between the shaft and the power transmitting member before the clutch member is operatively connected herewith, the said means comprising an annular fiange attached to the power transmission member in concentric relation to the shaft, the flange having a cylindrical friction surface, a plurality of angularly spaced friction shoes carried by the clutch member and mounted for longitudinal movement thereon, means for holding the friction shoes against rotary movement relative to the clutch member, resilient means 'for urging the friction shoes away from the friction surface, toggles,

interposed between the clutch member and each.

friction shoe, the toggles being normally so inare nearer the power transmission member than 'their inner ends, means for moving the clutch member towards the power transmission member, the adjacent member and the power adapted to interengage and form a positive driving connection, the friction surfaces of the fric- The Sudden f tion shoes being located in a circle which is normally spaced from the friction surface of the flange whereby the friction surfaces of the shoes and fiange can be brought into overlapping position, a stop for limiting the movement of the friction shoes towards the power transmission member, said stop becoming effective before the friction surfaces interengage, the stop being soposivsufficient relative rotary movement transmission member to permit the teeth] to mesh.

2. A clutch of the type employed for making .la positiveA driving connection between two coaxial members mounted for relative rotation about the same axis, comprising, in combination, a shaft, a power transmission member mounted for rotation about the axis of the shaft, a clutch 4 member slidably mounted on the shaft and held against rotation relative thereto, the adjacent portions of the clutch member and the power transmission member having teeth adapted to inerlock and form a positive driving connection, a sleeve mounted for longitudinal movement on the clutch memberbut held against rotary movement thereon by splines, a latching device for holding the sleeve in a predetermined longitudinal position relative to the clutch member, means for moving vthe clutch member and sleeve towards and awayfrom the power transmission member,

vthe latter having a Vcircular' friction surface, a

plurality of friction shoes carried by the sleeve, and mounted for radial and longitudinal movement thereon, each shoe having a friction surface adapted to cooperate with the friction surface on the power transmission member, means for moving the clutch member towards and away from the power transmission member, a stop for limiting j the movement of the friction shoes towards the power transmission member, means made effective when the stop functions to force the friction surfaces of the friction shoes against the frictionA surface of the power transmission member and for releasing the pressurek before the teeth'on the clutch member and on the power transmission member reach interlocking position, and means operative after the pressure between the friction surfaces has been released for releasng the latching means.

3. A clutch mechanism for interlocking a driven shaft with a driving power transmission member comprising a clutch member slidably but nonrotatably connected with the driven shaft, the adjacent surfaces of the clutch member and the power transmission member having teeth adapted to interlock, a friction clutch mechanism slidably but nonrotatably connected with the clutch member, a .positive latching device for holding the clutch member and the friction clutch mechanism against relative longi; tudinal movement, the friction clutch mechaynism and the power transmission member having cooperating friction surfaces, means for moving the clutch means and the friction clutch mechanism towards the power transmission member, means operated by the movement of the clutch member for bringing the friction surfaces into operative position and for forcing them together whereby the driving member and the driven shaft will be forced to rotate at the same speed, means operated by the further movement of the clutch member for releasing the friction clutch, and means operative by the still further movement of the clutch member for releasing the latching device before the teeth are brought into interengaging position.

JOSEPH P. RUTH. l GEORGE H. WOELBING. 

